Satellite communications in the past required precision alignment of the dish system, to comply with an aperture of 1.5 to 2.0 degrees maximum movement to be still adequately in the download or upload beam to permit proper data or signal transfer. This critical alignment can easily be thrown out of alignment during an earthquake, building or ground settling condition, or severe weather wind type calamity.
Satellite communications systems, once they are aligned, are considered to be more robust than terrestrial communications lines, especially when those lines are subject to events such as an earthquake, flood, or high wind condition.
Typically satellite systems are put into operation some time during their life span, typically 15 years for a specific satellite. Any corrective positioning, which has occurred on several satellites in orbit currently and in the past, requires direct technical support and re-alignment of the earth station equipment to take into account the positional movement.
Weather conditions are notorious for knocking out satellite earth stations and the smaller lower cost ones are very susceptible to weather outages. Larger network type earth stations usually or robust enough both in diameter and construction materials to withstand numerous weather events during their planned life span without causing unpreventable weather outages. Excluding rain fade which can only be addressed by larger dishes makes the smaller the dish more susceptible to snow and ice.
Typical wind loading on a dish, and more so on the larger the dish, can throw alignment, temporarily or permanently until a technician can re-align the earth station dish assembly. In view of extensive experience with conventional earth stations, it is believed that conventional earth stations lack any self compensating mechanism, except for those conventional stations that are fully motorized. Furthermore the awareness or call out for re-alignment of earth stations has been more than the norm in the past, especially on small aperture dishes such as a Very Small Aperture Terminal (VSAT), which is a two-way satellite ground station with a dish antenna that is smaller than 3 meters. Especially after a storm or serious snow fall, VSAT re-alignment may be needed.
Construction of most earth stations is made out of standard steel components with at the most only the primary bolts being made of stainless steel. This leads to much needed maintenance and painting needing to be the VSAT to be down to maintain the appearance, to reduce corrosion, and to maintain functionality of the typical earth station.
Snow and ice can be detrimental to proper earth station operation. At times, on larger systems, crews may even have to go out and sweep off the snow to stop its affect on the large dishes. Similarly the buildup of ice from snow melting on the warm electronics located at the feed assembly can cause serious ice loading lower on the dish. Smaller home or commercial VSAT type dishes are notorious for loosing satellite connectivity during heavy snow fall till someone goes out and cleans them off.